Cord strain relief means



Sept. 27, 1938. O. H. P IEPER CORD STRAIN RELIEF MEANS 2 Sheets-Sheet 1 Filed May 31, 1935 fave/aim": 05662? H fl'cjoafi 9% W awlww Sept. 27, 1938.

o. H.1PIEIPER 2,131,297

CORD STRAIN RELIEF MEANS Filed May 31, 1935 2 Sheets-Sheet 2 Patented Sept. 27, 1938 UNITED s'rArss PATENT oFFicE 6 Claims.

This invention relates to securing devices, and has to do with means for holding cords or analogous members attached to instruments associated with a dental unit or the like, in such manner as to facilitate freedom of use of the instruments.

It is known to provide dental units comprising a plurality of associated instruments, some electrical and some compressed air, to which are attached flexible cords which pass downward into the column of the unit and have associated therewith tension means, commonly Weights, which tend to hold the cords retracted within the column while permitting withdrawal of the cords in the use of the instruments. This arrangement, while possessing many good features, is open to the objection that the tension to which a Withdrawn cord is subjected interferes with the freedom of use of the instrument attached to that cord.

In my Patent No. 1,694,669, issued December 11, 1928, I have disclosed, in conjunction with a unit of the type above referred to, means for securing a withdrawn cord in such manner that the portion of the cord outward beyond the securing means is relieved of the pull of the tensioning means, the pull being exerted upon the remainder only of the cord and the securing means, so that freedom of use of the instrument attached to the cord is not interfered with. The securing means is in the form of spring clips which extend substantially horizontally and transversely of the column of the unit. These clips have proved to be highly efiicient for holding the instrument cords, but, due to their disposition, it may be necessary at times for the dentist to use both hands in Withdrawing a cord and inserting it into the clip. This is inconvenient, and at times may be objectionable, since there may be frequent instances when the dentist does not have both hands available for inserting the cord in the clip as, for example, when he is holding another instrument in the patients mouth. Also, clips of this character are not well adapted for use with units in which the instrument cords pass through a block or the like, which projects above the top wall of the table top of the unit column.

The instant invention is in the nature of an improvement over that of my above patent. It is directed to the provision of a dental unit having cord securing means associated therewith in such manner, and of such character, that a withdrawn cord can be inserted into the securing means with facility and, if necessary, with the use of but one hand. A further object is to provide securing means so related to the unit that.

a cord may be inserted into the securing means by a simple downward movement as a natural continuation of the act of withdrawing the cord from the unit. It is also an object toprovide improved cord securing means of simple and inexpensive construction and neat appearance. Further objects and advantages of my invention will appear from the detail description.

In the draw.ings: v

Figure l-is a fragmentary isometric side view of the upper portion of a dentalunit embodying my invention; Figure 2 is a side view, partly broken away and in section, of a dental unit embodying my invention, showing one of the instrument cords withdrawn and secured by the clamping means, certain of the instruments being omitted for clearness of illustration;

Figure 3 is a front view of the clamping means and the associated supporting bracket therefor;

Figure 4 is a section taken substantially on line LA of Figure 3, parts being broken away;

Figure 5 is a view similarto Figure 3, but with the housing casing of the clamping means removed; and g Figure 6 is a back View of the clamping'means casing.

I have shown my invention, by way of example, as applied to the dental unit disclosed in my copending application for Dental unit, Serial No. 5,947, filed February 11, 1935. It will be understood, however, that my invention may be applied to any other suitable dental unit.

In Figures 1 and 2 of the drawings, I'have shown a dental unit comprising a hollow column it! provided at its upper end with a downwardly and forwardly inclined table top H in which is mounted an instrument block 52. This block l2, which may be considered as part of the table top, is provided with suitable openings, through which pass flexible cords, which are attached, in a known manner, to instruments seating in appropriate recesses or sockets formed in block l2. The instruments mounted in the block maybe a hot air syringe :4, hand pieces or switch handles i5 adaptedto receive in their upper ends suitable electrical instruments, and an air cut- 01f nozzle 96, of known type, adapted for quick attachment to atomizers. It will be understood that the cords attached to instruments It and it, which cords are not shown, are in the form of rubber tubing or air hose, and are connected to a suitable source of compressed air, and the cords attached to switch handles l5, one of which latter cords is shown and identified by reference number l3, are electrical cords connected to a source of electrical energy; as is Well known in the art.

The air hose and the cords l3 have associated therewith means for urging them inward of column I6, so as normally to retain the air hose and the electrical cords retracted and the instruments seated in block 12, while permitting withdrawal of the cords and the air hose in the use of the instruments. In the embodiment of my invention illustrated by way of example, each air hose and each cord i3 passes about and beneath wheel ll of a pulley and weight member 8. The other end of each air hose and each cord 13 is suitably anchored within column M, as is well known in the art, and members I 8 maintain them under tension effective to return the air hose and the cords to retracted position andhold the associated instruments seated in block l2, while permitting withdrawal of the air hose and cords in the use of the instruments.

A bracket I9 is suitably secured, as by screw means, to a lug !2a of block [2. This bracket is shaped as shown, and comprises an upwardly projecting arm 20 carrying, at its upper end, an integral flat plate 2! of rectangular shape, which plate is disposed substantially vertical, projects above the table top of column ID, and extends transversely of and in substantial parallelism with the front wall of the column if). A box-like ornamental casing 22 is mounted upon plate 2| in a suitable manner, as by means of screws 23 passing through plate 2!; and threading into bosses 24 projecting rearward from the front wall of the casing. The top and the side walls of casing 22 fit snugly about the top and the sides of plate 2| and facilitate accurate positioning thereon of the casing. Bosses 24, in addition to receiving screws 23, also serve to space the front wall of casing 22 the proper distance from plate 2|. Casing 22 is preferably formed as shown, but may be of any other suitable or preferred construction.

The upper corners 22a of casing 22 are preferably rounded, as shown. Clamping members 25, disposed adjacent side walls 26 of casing 22, are pivoted, adjacent their lower ends, on pins 21 extending from front to back of the casing and suitably secured in bosses 28formed integral with plate 2| at the lower corners thereof. The forward portions of these pins seat in bosses 29 formed integral with the front wall of casing 22,

at the lower corners thereof, aligned with bosses 28. The side walls of casing 22 terminate above bosses 29, at 26a, to accommodate the clamping members, as shown. Each clamping member 25 comprises an arm 25a of approximately elongated S-shape, and an integral finger 25?) which curves inward and upward within casing 22 from the lower end of arm 25a. A tension coil spring 30 connects fingers 25b and yieldingly urges clamping arms 25a toward side walls 26 of casing 22, with which the arms 25 cooperate for clamping an electrical cord i3 inserted between either arm and the adjacent side wall of the casing. Casing 22 thus provides a housing for fingers 25b and spring 30, and cooperates with arms 25 for clamping the cords I3.

The upper portion of each arm 25 projects above the adjacent side wall 26 of casing 22, and is curved upward and outward of the casing, laterally thereof, as shown. The rounded corner 22a of the casing 22 and the upper portion of the adjacent arm 25 thus define a downwardly converging passage 3l, which is conducive to insertion of a cord I3 downward between arm 25 and the side wall 26 of the casing with facility.

Casing 22 is preferably disposed at the midlength of block I 2, with the cord clamping means, comprising arms 25 and side walls 26 of casing 22, in substantial alignment with the switch handles l5, since these latter are the instruments most frequently used for any considerable length of time. In use, the selected switch handle, with its associated instrument, is removed from block i2, the attached cord l3 being withdrawn from column In to the desired extent. The cord l3, as withdrawn, extends slightly above and adjacent the clamping means, as indicated by the position of cord l8 shown in dot and dash lines in Figure 1. Cord I3 is then swung downward, as a natural continuation of the withdrawing operation, as indicated by the dotted arrow (1 of Figure 1, so as to be inserted between one of the clamping arms 25 and the adjacent side wall 26 of casing 22. During this operation, which may readily be performed with one handyif desired, the upper projecting portion of arm 25 serves as a guide for the cord. After the cord contacts the upper portion of arm 25, it may be pulled laterally so as to move the arm away from the easing, facilitating entry of the cord between the arm and the adjacent casing wall, if desired.

The tension of spring 30 is such that cord [3 is effectively clamped between arm 25 and the side wall 26 of casing 22, so that the pull of the cor-d tensioning means is taken by the clamp and the portion of the cord disposed inward of the clamp, the portion ofthe cord disposed outward beyond the clamp being relieved of tension for freedom of use of the attached instrument.

As a general rule, the instruments l4 and I6, at the ends of block l2, are only used momentarily, and it is not ordinarily necessary to relieve the air hose attached to these instruments from the pull of the tensioning means. However, if desired, or in exceptional cases, the air hose attached to either of the instruments l4 and i6 may be inserted into the clamping means so as to be held thereby, in substantially the manner above described with respect to the electrical cords l3. This operation is obvious and need not be described in detail.

In order to release a cord l3 from the clamping means, it is only necessary to pull the cord upward, and if desired laterally away from casing 22, until it passes from between arm 25 and the side wall of the casing. 'The cord may then be retracted within-the column I0, and the instrument returned to block I 2, by the cord tensioning means. This operation of releasing the cord and returning the instrument to block 12 may also be performed with one hand, when desired or necessary. Obviously, an air hoseof either of the instruments I 4 and I6, if held by the clamping means, may be released therefrom in the same manner as the above.

While I have disclosed the clamping means of my invention, by way of example, as applied to a dental unit to which it is related in a particular manner, it is not limited to use with the particular unit shown. In its broader aspects, my invention comprehends clamping means of the character shown used with a suitable support for dental or like instruments having attached thereto flexible cords or hose having associated therewith tensioning means. Also, the clamping means itself may be used for various purposes, as will be obvious.

It will be understood, by those skilled in the art, that changes in construction and arrangement of parts of my invention may be resorted to, without departing from the field and scope thereof, and I intend to include all such variations, as fall within the scope of the appended claims, in this application in which the preferred form only of my invention is disclosed.

What I claim is:-

1. In combination in clamping means of the character described, a box-like casing comprising front and rear and side walls, clamping members adjacent the sides of said casing and cooperating therewith for clamping an article inserted between said casing and either of said members, and means within said casing yield-ingly urging said members toward said side walls of said casing.

2. In combination in clamping means of the character described, a box-like casing comprising front and rear and side walls, clamping members disposed adjacent and extending lengthwise of the sides of said casing, and means within said casing common to said members yieldingly urging them toward the sides of said casing, said clamping members cooperating with the sides of said casing for clamping articles inserted therebetween.

3. In combination in clamping means of the character described, a box-like casing comprising front and rear and side walls, clamping members disposed adjacent and extending lengthwise of the sides of said casing and projecting above the latter, each of said clamping members being pivoted adjacent its lower end on an axis extending from front to back of said casing, and means within said casing yieldingly urging said clamping members about their pivots toward the sides of said casing.

4. In combination in clamping means of the character described, a box-like casing comprising front and rear and side walls, clamping members disposed adjacent and extending lengthwise of the side walls of said casing exterior thereof, each of said members being pivoted adjacent its lower end on an axis extending from front to back of the casing and each being provided with an element extending upward and inward within the casing, and a tension spring within said casing connecting said elements and yieldingly urging said members toward said side walls of said casing.

5. In combination in a dental unit, a supporting column, an instrument supporting member mounted on the upper end of said column, dental instruments mounted in said member, flexible cords attached to said instruments and passing upward through said column and supporting member in the use of said instruments, yielding tension means urging said cords inward of said column, a box-like casing mounted adjacent and in front of said supporting member with its top wall thereabove for movement over said top wall of a withdrawn cord, clamping arms at the sides of said casing extending thereabove for confining the cord laterally of the casing during movement over the top thereof, said arms being movable at their upper ends toward and away from the sides of the casing in a plane substantially parallel to the front of said column, and means housed within said casing for yieldingly urging said arms toward the sides of said casing.

6. In combination in a dental unit, a supporting column, an instrument supporting member mounted on the upper end of said column, dental instruments mounted in said member, flexible cords attached to said instruments and passing upward through said column and supporting member in the use of said instruments, yielding tension means urging said cords inward. of said column, a structure comprising a top wall and side walls mounted adjacent and in front of said supporting member with its top wall thereabove for movement over said top wall of a withdrawn cord, clamping arms at the sides of said structure extending thereabove for confining the cord laterally of said structure during movement over the top thereof, said arms being movable at their upper ends toward and away from said side walls of said structure in a plane substantially parallel to the front of said column, and means yieldingly urging said arms toward said side walls.

OSCAR H. PIEPER. 

